摘要 |
<p>In the test unit, water for treatment is extracted from an inner circuit and supplied to an outer concentric circuit, setting up defined concentric flow. An Independent claim is included for a corresponding test unit. It comprises a reactor (1) with concentric outer- and inner rings (2, 3). A solid bed intervenes between them, comprising e.g. earth, sand or gravel. It has a gas-tight upper capping (4) with plant openings (5) and a base (11). Inlet- and outlet- openings (12, 13) and -lines (6, 7) are provided. Preferred Features: A pump is used to start up the inner circuit. A supply pump is started, such that waste water for investigation is mixed into the inner circuit. A controller sets a defined level in the reactor, with excess water flowing out. Residence time is adjusted by varying the rate of supply as required. Mixing is adjusted by independent variation of the recirculation flowrate, which exceeds that of supply.</p> |